Chrysler 2004 Pacifica User manual

TABLE OF CONTENTS
1.0 INTRODUCTION .........................................................1
1.1 SYSTEM COVERAGE ...............................................1
1.2 SIX-STEP TROUBLESHOOTING PROCEDURE ..........................1
2.0 IDENTIFICATION OF SYSTEM .............................................1
3.0 SYSTEM DESCRIPTION AND FUNCTIONAL OPERATION ......................1
3.1 TEVES MARK 25 SYSTEM DESCRIPTION ..............................1
3.2 TRACTION CONTROL SYSTEM (TCS) DESCRIPTION (IF EQUIPPED).......1
3.3 SYSTEM COMPONENTS.............................................1
3.3.1 ABS AND BRAKE WARNING INDICATORS ......................2
3.3.2 CONTROLLER ANTILOCK BRAKE (CAB) .......................2
3.3.3 HYDRAULIC CONTROL UNIT .................................2
3.3.4 ABS SWITCHES/SENSORS...................................3
3.3.5 ABS INITIALIZATION ........................................3
3.3.6 ABS DIAGNOSTIC MODE ....................................3
3.3.7 TRACTION CONTROL OPERATION (IF EQUIPPED) ..............4
3.5 DIAGNOSTIC TROUBLE CODES ......................................4
3.6 FREEZE FRAME....................................................4
3.7 DRBIIITERROR MESSAGES AND BLANK SCREEN ......................4
3.7.1 DRBIIITDOES NOT POWER UP...............................4
3.7.2 DISPLAY IS NOT VISIBLE ....................................4
4.0 DISCLAIMERS, SAFETY, WARNINGS .......................................5
4.1 DISCLAIMERS......................................................5
4.2 SAFETY...........................................................5
4.2.1 TECHNICIAN SAFETY INFORMATION..........................5
4.2.2 VEHICLE PREPARATION FOR TESTING........................5
4.2.3 SERVICING SUB-ASSEMBLIES ...............................5
4.2.4 DRBIIITSAFETY INFORMATION...............................5
4.3 WARNINGS ........................................................6
4.3.1 VEHICLE DAMAGE WARNINGS ...............................6
4.3.2 ROAD TESTING A COMPLAINT VEHICLE .......................6
4.4 DIAGNOSIS........................................................6
5.0 REQUIRED TOOLS AND EQUIPMENT ......................................6
6.0 GLOSSARY OF TERMS...................................................6
7.0 DIAGNOSTIC INFORMATION AND PROCEDURES ............................9
BRAKES (CAB)
BATTERY VOLTAGE OUT OF RANGE ......................................10
BCM MESSAGES NOT RECEIVED.........................................12
CAB INTERNAL FAILURE ................................................13
INSTRUMENT CLUSTER BULB FAILURE ...................................15
LEFT FRONT SENSOR CIRCUIT FAILURE ..................................17
LEFT REAR SENSOR CIRCUIT FAILURE ...................................17
RIGHT FRONT SENSOR CIRCUIT FAILURE.................................17
RIGHT REAR SENSOR CIRCUIT FAILURE ..................................17
LEFT FRONT WHEEL SPEED SIGNAL FAILURE .............................22
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TABLE OF CONTENTS - Continued
LEFT REAR WHEEL SPEED SIGNAL FAILURE ..............................22
RIGHT FRONT WHEEL SPEED SIGNAL FAILURE............................22
RIGHT REAR WHEEL SPEED SIGNAL FAILURE .............................22
MIC MESSAGES NOT RECEIVED .........................................25
PCI BUS COMMUNICATION FAULT ........................................27
PCI BUS LOOPBACK FAILURE............................................30
PCI BUS SHORTED TO GROUND .........................................32
PCI BUS SHORTED TO VOLTAGE.........................................35
PCI HARDWARE FAILURE ...............................................38
PCM MESSAGES NOT RECEIVED.........................................40
PUMP MOTOR CIRCUIT FAILURE .........................................42
COMMUNICATION
*NO RESPONSE FROM CONTROLLER ANTILOCK BRAKE ....................44
VERIFICATION TESTS
VERIFICATION TESTS...................................................46
8.0 COMPONENT LOCATIONS...............................................47
8.1 CONTROLLER ANTILOCK BRAKE (CAB) ..............................47
8.2 DATA LINK CONNECTOR ...........................................47
8.3 FUSES...........................................................47
8.4 TRACTION CONTROL SWITCH ......................................48
8.5 INDICATORS......................................................48
8.6 BRAKE LAMP SWITCH .............................................48
9.0 CONNECTOR PINOUTS .................................................49
BRAKE LAMP SWITCH - BLACK 6 WAY ....................................49
CONTROLLER ANTILOCK BRAKE - BLACK 47 WAY..........................49
DATA LINK CONNECTOR - BLACK 16 WAY .................................50
FUSES (IPM)...........................................................52
TRACTION CONTROL SWITCH - BLACK 3 WAY .............................53
WHEEL SPEED SENSOR-LEFT FRONT - LT. GRAY 2 WAY ....................53
WHEEL SPEED SENSOR-LEFT REAR - LT. GRAY 2 WAY......................53
WHEEL SPEED SENSOR-RIGHT FRONT - LT. GRAY 2 WAY ...................53
WHEEL SPEED SENSOR-RIGHT REAR - LT. GRAY 2 WAY ....................54
10.0 SCHEMATIC DIAGRAMS.................................................55
10.1 TEVES MARK 25 CONTROLLER ANTILOCK BRAKE – ABS ...............55
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1.0 INTRODUCTION
The procedures contained in this manual include
all the specifications, instructions, and graphics
needed to diagnose the 2004 Chrysler Pacifica Mark
25 Antilock Braking System (ABS), and Mark 25
Antilock Braking System with Traction Control.
The diagnostics in this manual are based on the
failure condition or symptom being present at time
of diagnosis.
Please follow the recommendations below when
choosing your diagnostic path.
1. First make sure the DRBIIItis communicating
with the CAB. If the DRBIIItdisplays a “No
Response” condition, you must diagnose that
first.
2. Read DTC’s (diagnostic trouble codes) with the
DRBIIIt.
3. If no DTC’s are present, identify the customer
complaint.
4. Once the DTC or customer complaint is identi-
fied, locate the matching test in the Table of
Contents and begin to diagnose the symptom.
All component location views are in Section 8.0.
All connector pinouts are in Section 9.0. All sche-
matics are in Section 10.0.
An asterisk (*) placed before the symptom de-
scription indicates a concern with no associated
DTC.
When repairs are required, refer to the appropri-
ate service manual for the proper removal and
repair procedure.
Diagnostic procedures change every year. New
diagnostic systems may be added; carry over sys-
tems may be enhanced. READ THIS MANUAL
BEFORE TRYING TO DIAGNOSE A VEHICLE
CODE. It is recommended that you review the
entire manual to become familiar with all new and
changed diagnostic procedures.
After using this book, if you have any comments
or recommendations, please fill out the form at the
back of the book and mail it back to us.
1.1 SYSTEM COVERAGE
This diagnostic procedure manual covers the an-
tilock braking system (ABS), and the traction con-
trol system (TCS) found on: Chrysler Pacifica.
1.2 SIX-STEP TROUBLESHOOTING
PROCEDURE
Diagnosis of the controller antilock brake module
is done in six basic steps:
•verification of complaint
•verification of any related symptoms
•symptom analysis
•problem isolation
•repair of isolated problem
•verification of proper operation
2.0 IDENTIFICATION OF
SYSTEM
Vehicles equipped with the Teves Mark 25 an-
tilock brake system can be identified by the pres-
ence of the controller antilock brake module located
beneath the master cylinder.
The presence of the Traction Control system is
indicated by the switch on top of the center console
by shifter.
3.0 SYSTEM DESCRIPTION AND
FUNCTIONAL OPERATION
3.1 TEVES MARK 25 SYSTEM
DESCRIPTION
The controller antilock brake module is used to
monitor wheel speeds and to modulate (control)
hydraulic pressure in each brake channel. The
modulated hydraulic pressure is used to prevent
wheel lock-up during braking.
The Teves Mark 25 system uses a diagonal split
hydraulic brake system. In the standard brake
mode the master cylinder primary circuit supplies
pressure to the right front and left rear wheel
brakes, and the secondary master cylinder circuit
supplies pressure to the left front and right rear
wheel brakes.
All vehicles equipped with ABS use Electronic
Variable Brake Proportioning (EVPB) to balance
front-to-rear braking when brakes are applied in
the partial braking range.
3.2 TRACTION CONTROL SYSTEM (TCS)
DESCRIPTION (IF EQUIPPED)
The main purpose of traction control is to reduce
wheel slip and maintain traction at the driven
wheels when road surfaces are slippery. The trac-
tion control system reduces wheel slip by braking
the wheel that is losing traction. The system is
designed to operate at speeds below 56 km/h (35
mph).
3.3 SYSTEM COMPONENTS
ABS
•controller antilock brake (CAB)
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•vacuum booster
•master cylinder
•ABS integrated electronic control module/
hydraulic control unit (HCU), 1 pump motor.
•4 wheel speed sensor/tone wheel assemblies
•ABS warning indicator
•fuses and wiring harness
•fluid reservoir
•brake lamp switch
ABS With Traction Control
•CAB with Traction Control programming
•HCU with four additional control valves.
•TCS Switch
•TCS indicator
3.3.1 ABS AND BRAKE WARNING
INDICATORS
The amber ABS warning indicator is located in
the instrument cluster. It is used to inform the
driver that the antilock function has been turned
off. The ABS warning indicator is controlled by the
CAB. The CAB controls the lamp with a command
over the PCI bus.
TheABS Warning Indicator will remain lit during
every key cycle until a circuit or component fault is
repaired and the CAB no longer detects the fault.
After repair of a sensor signal fault or a pump motor
fault, the CAB must sense all four wheels at 25
km/h (15 mph) before it will extinguish theABS and
TCS Indicator.
The Instrument Cluster will illuminate the ABS
Warning Indicator if it loses communication with
the CAB.
The red BRAKE warning indicator is also located
in the instrument cluster. It can be activated in
several ways. Application of the parking brake or a
low fluid signal from the fluid level switch located in
the master cylinder reservoir will cause the indica-
tor to come on.
3.3.2 CONTROLLER ANTILOCK BRAKE
(CAB)
The Controller Antilock Brake (CAB) is a
microprocessor-based device that monitors wheel
speeds and controls the antilock functions. The
CAB contains two microprocessors that receive
identical sensor signals and then independently
process the information. The results are then com-
pared to make sure that they agree. Otherwise, the
CAB will turn off the antilock and turn on the ABS
amber warning indicator.
The primary functions of the CAB are to:
•detect wheel locking tendencies
•control fluid pressure modulation to the brakes
during antilock stop
•monitor the system for proper operation
•manage traction control functions
•provide communication to the DRBIIItwhile in
diagnostic mode
•store diagnostic information in non-volatile mem-
ory
The CAB continuously monitors the speed of each
wheel. When a wheel locking tendency is detected,
the CAB will command the appropriate valve to
modulate brake fluid pressure in its hydraulic unit.
Brake pedal position is maintained during an an-
tilock stop by being a closed system. The CAB
continues to control pressure in individual hydrau-
lic circuits until a wheel locking tendency is no
longer present. The CAB turns on the pump motor
during an antilock stop.
The antilock brake system is constantly moni-
tored by the CAB for proper operation. If the CAB
detects a system malfunction, it can disable the
antilock system and turn on the ABS warning
indicator. If the antilock function is disabled, the
system will revert to standard base brake system
operation.
The CAB inputs include the following:
•diagnostic communication
•four wheel speed sensors
•three power feeds: valve, pump, and microproces-
sor
•brake lamp switch
•traction control switch (BCM via PCI Bus)
The CAB outputs include the following:
•ABS warning indicator actuation
•12 volts power to wheel speed sensors
•valve actuation
•diagnostic communication
•PCI bus communication
•traction control lamp illumination
3.3.3 HYDRAULIC CONTROL UNIT
The hydraulic control unit (HCU) contains the
valve block assembly, and pump/motor assembly.
The HCU is attached to the CAB.
Valve Block Assembly: The valve block assem-
bly contains valves with four inlet valves and four
outlet valves. The inlet valves are spring-loaded in
the open position and the outlet valves are spring
loaded in the closed position. During an antilock
stop, these valves are cycled to maintain the proper
slip ratio for each wheel. If a wheel detects slip, the
inlet valve is closed to prevent and further pressure
increase. Then the outlet valve is opened to release
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the pressure to the accumulators until the wheel is
no longer slipping. Once the wheel is no longer
slipping, the outlet valve is closed and the inlet
valve is opened to reapply pressure. If the wheel is
decelerating within its predetermined limits (prop-
er slip ratio), the inlet valve will close to hold the
pressure constant. On vehicles which are equipped
with a traction control system, there are four addi-
tional valves, two isolate the master cylinder and
two shuttle. During a traction control event the
brakes are applied to reduce wheel slippage.
Pump Motor Assembly: The pump motor as-
sembly provides the extra amount of fluid needed
during antilock braking. The pump is supplied fluid
that is released to the accumulators when the outlet
valve is opened during an antilock stop. The pump
is also used to drain the accumulator circuits after
the antilock stop is complete. The pump is operated
by an integral electric motor. This motor is con-
trolled by the CAB. The CAB may turn on the pump
motor when an antilock stop is detected. The pump
continues to run during the antilock stop and is
turned off after the stop is complete. Under some
conditions, the pump motor will run to drain the
accumulators during the next drive off. The CAB
monitors the pump motor operation internally.
3.3.4 ABS SWITCHES/SENSORS
Master Cylinder: The master cylinder is a stan-
dard tandem compensating port design forABS and
non ABS systems. Traction control vehicles use a
dual center port master cylinder. For proper trac-
tion control operation the standard master cylinder
must not be used.
A fluid level switch is located in the master
cylinder fluid reservoir. The switch closes when a
low fluid level is detected. The fluid level switch
turns on the brake warning indicator by grounding
the indicator circuit. This switch does not disable
the ABS system.
Wheel Speed Sensors and Tone Wheels: One
active wheel speed sensor (WSS) is located at each
wheel. The sensors use an electronic principle
known as magneto-resistive to help increase perfor-
mance, durability and low speed accuracy. The
sensors convert wheel speed into a small digital
signal. A toothed gear tone wheel serves as the
trigger mechanism for each sensor.
The CAB sends 12 volts to power an Integrated
Circuit (IC) in the sensor. The IC supplies a con-
stant 7 mA signal to the CAB. The relationship of
the tooth on the tone wheel to the permanent
magnet in the sensor, signals the IC of the sensor to
toggle a second 7 mA power supply on or off. The
output of the sensor, sent to the CAB, is a DC
voltage signal with changing voltage and current
levels. The CAB monitors the changing amperage
(digital signal) from each wheel speed sensor. The
resulting signal is interpreted by the CAB as the
wheel speed.
Because of internal circuitry, correct wheel
speed sensor function cannot be determined
by a continuity or resistance check through
the sensor.
Correct antilock system operation is dependent
on tone wheel speed signals from the wheel speed
sensors. The vehicle’s wheels and tires should all be
the same size and type to generate accurate signals.
In addition, the tires should be inflated to the
recommended pressure for optimum system opera-
tion. Variation in wheel and tire size or significant
variations in inflation pressure can produce inaccu-
rate wheel speed signals; however, the system will
continue to function when using the correct factory
mini-spare.
3.3.5 ABS INITIALIZATION
System initialization starts when the key is
turned to “run”. At this point, the CAB performs a
complete self-check of all electrical components in
the antilock systems.
Between 8-17 km/h (5-10 mph), a dynamic test is
performed. This will momentarily cycle the inlet
and outlet valves, check wheel speed sensor cir-
cuitry, and run the pump motor at 25 km/h (15
mph). The CAB will try to test the pump motor. If
the brake pedal is applied the test will be run at 40
km/h (24 mph) regardless of brake switch state. If,
during the dynamic test, the brake pedal is applied,
the driver may feel the test through brake pedal
pulsations. This is a normal condition.
If any component exhibits a trouble condition
during system initialization or dynamic check, the
CAB will illuminate theABS warning indicator and
TCS Indicator if equipped.
3.3.6 ABS DIAGNOSTIC MODE
To enter diagnostic mode, a vehicle speed must be
below 10 km/h (6 mph) and no ABS condition
present. If vehicle speed is not below 10 km/h
(6 mph), a “No Response” message could be dis-
played by the DRBIIIt. The following are charac-
teristics of diagnostic mode:
– The amber ABS warning indicator will blink
rapidly. If a hard trouble code, such as Battery
Voltage Out of Range code is present, the
indicator will be illuminated without blinking
until the trouble condition is cleared.
– Antilock operation is disabled.
– The HCU valves cannot be actuated when the
vehicle speed is above 8 km/h (5 mph). If valve
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actuation is attempted above 8 km/h (5 mph), a
“No Response” message will be displayed on
the DRBIIIt.
3.3.7 TRACTION CONTROL OPERATION
(IF EQUIPPED)
The Controller Antilock Brake (CAB) monitors
wheel speeds. If, during acceleration, the module
detects front (drive) wheel slip and the brakes are
not applied, the CAB will enter traction control
mode. Traction control works in the following order
when drive wheel slip is detected.
1. Close the (normally open) isolation valves.
2. Start pump/motor and supply volume/pressure
to front hydraulic circuits (pump runs continu-
ously during traction control).
3. Open and close build and decay valves to main-
tain minimum wheel slip and maximum trac-
tion.
The cycling of the build and decay valves is
similar to the ABS except that they work to control
wheel spin by applying brakes. ABS function is to
control wheel skid by releasing brakes.
Two pressure relief valves allow excess fluid vol-
ume to return to the reservoir when not used by the
build/decay cycles. These are required because the
pump supplies more volume than the traction con-
trol system requires.
If at any time the brake pedal is applied during a
traction control cycle, the brake lamp switch will
trigger the CAB to switch off the traction control.
The traction control system will be enabled at
each ignition cycle. It may be turned off by depress-
ing the Traction Control Switch. The traction con-
trol system function lamp will illuminate Traction
Control immediately upon depressing the traction
control switch button. The indicator will illuminate
during a traction control event.
If the CAB calculates that the brake tempera-
tures are high, the traction control system will
become inoperative until a time-out period has
elapsed. When in this thermal protection mode, the
traction control indicator will illuminate; however,
a fault will not be registered. The TCS switch is
sensed by the BCM.
3.5 DIAGNOSTIC TROUBLE CODES
The Controller Antilock Brake may report any of
several Diagnostic Trouble Codes (DTC)s.
3.6 FREEZE FRAME
Freeze Frame takes a “snapshot” of specific vehi-
cle information the instant an ABS failure is recog-
nized and stores this information into the CAB
memory. This information can be accessed using the
DRBIIItto help diagnose the fault. Freeze Frame
will capture the first time failure or only a new
failure that occurs during the current ignition cycle.
3.7 DRBIIITERROR MESSAGES AND
BLANK SCREEN
Under normal operation, the DRBIIItwill dis-
play one of only two error messages:
– User-Requested WARM Boot or User-
Requested COLD Boot.
If the DRBIIItshould display any other error
message, record the entire display and call the
STAR Center. This is a sample of such an error
message display:
ver: 2.14
date: 26 Jul93
file: key_itf.cc
date: Jul 26 1993
line: 548
err. 0x1
User-Requested COLD boot
Press MORE to switch between this display
and the application screen.
Press F4 when done noting information.
3.7.1 DRBIIITDOES NOT POWER UP
If the LED’s do not light or no sound is emitted at
start up, check for loose cable connections or a bad
cable. Check the vehicle battery voltage (data link
connector cavity 16). A minimum of 11 volts is
required to adequately power the DRBIIIt.
If all connections are proper and the vehicle
battery is fully charged, an inoperative DRBIIIt
may be the result of faulty cable or vehicle wiring.
3.7.2 DISPLAY IS NOT VISIBLE
Low temperatures will affect the visibility of the
display. Adjust the contrast to compensate for this
condition.
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4.0 DISCLAIMERS, SAFETY,
WARNINGS
4.1 DISCLAIMERS
All information, illustrations, and specifications
contained in this manual are based on the latest
information available at the time of publication.
The right is reserved to make changes at any time
without notice.
4.2 SAFETY
4.2.1 TECHNICIAN SAFETY INFORMATION
WARNING: ENGINES PRODUCE CARBON
MONOXIDE THAT IS ODORLESS, CAUSES
SLOWER REACTION TIME, AND CAN LEAD
TO SERIOUS INJURY. WHEN THE ENGINE IS
OPERATING, KEEP SERVICE AREAS WELL
VENTILATED OR ATTACH THE VEHICLE
EXHAUST SYSTEM TO THE SHOP EXHAUST
REMOVAL SYSTEM.
Set the parking brake and block the wheels before
testing or repairing the vehicle. It is especially
important to block the wheels on front-wheel drive
vehicles; the parking brake does not hold the drive
wheels.
When servicing a vehicle, always wear eye pro-
tection, and remove any metal jewelry such as
rings, watchbands or bracelets that might make an
inadvertent electrical contact.
When diagnosing a chassis problem, it is impor-
tant to follow approved procedures where applica-
ble. These procedures can be found in the service
manual. Following these procedures is very impor-
tant to the safety of individuals performing diag-
nostic tests.
4.2.2 VEHICLE PREPARATION FOR
TESTING
Make sure the vehicle being tested has a fully
charged battery. If is does not, false diagnostic codes
or error messages may occur.
4.2.3 SERVICING SUB-ASSEMBLIES
Some components of the chassis system are in-
tended to be serviced as an assembly only. Attempt-
ing to remove or repair certain system sub-
components may result in personal injury and/or
improper system operation. Only those components
with approved repair and installation procedures in
the service manual should be serviced.
4.2.4 DRBIIITSAFETY INFORMATION
WARNING: EXCEEDING THE LIMITS OF THE
DRBIIITMULTIMETER IS DANGEROUS. IT
CAN EXPOSE YOU TO SERIOUS OR
POSSIBLY FATAL INJURY. CAREFULLY
READ AND UNDERSTAND THE CAUTIONS
AND THE SPECIFICATION LIMITS.
•Follow the vehicle manufacturer’s service speci-
fications at all times.
•Do not use the DRBIIItif it has been damaged.
•Do not use the test leads if the insulation is
damaged or if metal is exposed.
•To avoid electrical shock, do not touch the test
leads, tips, or the circuit being tested.
•Choose the proper range and functions for the
measurement. Do not try voltage or current mea-
surements that may exceed the rated capacity.
•Do not exceed the limits shown in the table below:
FUNCTION INPUT LIMIT
Volts 0 - 500 peak volts AC
0 - 500 volts DC
Ohms (resistance)* 0 -1.12 megohms
Frequency Measured
Frequency Generated 0-10kHz
Temperature -58 - 1100°F
-50 - 600°C
* Ohms cannot be measured if voltage is present.
Ohms can be measured only in a non-powered
circuit.
•Voltage between any terminal and ground must
not exceed 500v DC or 500v peak AC.
•Use caution when measuring voltage above 25v
DC or 25v AC.
•Use the low current shunt to measure circuits up
to 10A. Use the high current clamp to measure
circuits exceeding 10A.
•When testing for the presence of voltage or cur-
rent, make sure the meter is functioning cor-
rectly. Take a reading of a known voltage or
current before accepting a zero reading.
•When measuring current, connect the meter in
series with the load.
•Disconnect the live test lead before disconnecting
the common test lead.
•When using the meter function, keep the
DRBIIItaway from spark plug or coil wires to
avoid measuring error from outside interference.
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4.3 WARNINGS
4.3.1 VEHICLE DAMAGE WARNINGS
Before disconnecting any control module, make
sure the ignition is ‘‘off’’. Failure to do so could
damage the module.
When testing voltage or continuity at any control
module, use the terminal side (not the wire end) of
the connector. Do not probe a wire through the
insulation, this will damage it and eventually cause
it to fail because of corrosion.
Be careful when performing electrical tests so as
to prevent accidental shorting of terminals. Such
mistakes can damage fuses or components. Also, a
second code could be set, making diagnosis of the
original problem more difficult.
4.3.2 ROAD TESTING A COMPLAINT
VEHICLE
Some complaints will require a test drive as part
of the repair verification procedure. The purpose of
the test drive is to try to duplicate the diagnostic
code or symptom condition.
WARNING: BEFORE ROAD TESTING A
VEHICLE, BE SURE THAT ALL
COMPONENTS ARE REASSEMBLED.
DURING THE TEST DRIVE, DO NOT TRY TO
READ THE DRB SCREEN WHILE IN MOTION.
DO NOT HANG THE DRBIIITFROM THE
REAR VIEW MIRROR OR OPERATE IT
YOURSELF. HAVE AN ASSISTANT
AVAILABLE TO OPERATE THE DRBIIIT.
4.4 DIAGNOSIS
1. Your diagnostic test procedure must begin with a
thorough visual inspection of the system in ques-
tion for damaged components or disconnected
connectors. For ABS the brake lamps must be
operational prior to continuing.
2. Connect the DRBIIItto the data link connector,
which is located under the dash to the left of the
steering column. If the DRBIIItdoes not power
up, check the power and ground supplies to the
connector.
3. Turn the ignition on. Select the system in ques-
tion. If the DRBIIItdisplays “No Response”
condition you must diagnose that first.
4. Read and record all diagnostic trouble codes. For
ABS if the “CAB Power Feed Circuit” diagnostic
trouble code is present, it must be repaired prior
to addressing any other DTC’s. If any additional
DTC’s are present, proceed to the appropriate
test by locating the matching test in the Table of
Contents and begin to diagnose the symptom.
5. For ABS if there are no diagnostic trouble codes
present, identify the customer complaint. Select
“Inputs/Outputs” and read the brake switch in-
put as you press and release the brake pedal. If
the display does not match the state of the pedal,
diagnose the symptom. If a problem exists with
the amber “ABS” warning indicator or the red
“Brake” indicator exists, diagnose the symptom.
Read the traction control switch input as you
press and release the switch. If the display does
not match the state of the indicator, diagnose the
symptom.
6. If no other problems are found, it will be neces-
sary to road test the vehicle. Perform several
antilock stops from above 50 Km/h (30 mph) and
then repeat step 4. If any diagnostic trouble
codes are present, proceed to the appropriate
test.
7. The following conditions should be considered
“NORMAL” operation, and no repairs should be
attempted to correct them.
– Brake pedal feedback during an ABS stop
(clicking, vibrating).
– Clicking, groaning or buzzing at 25 Km/h (15
mph) or 40 Km/h (24 mph) (drive off self test).
– Groaning noise during an ABS stop.
– Slight brake pedal drop and pop noise when
ignition is initially turned on.
– Brake pedal ratcheting down at the end of an
ABS stop.
8. If the complaint is ABS “cycling” at the end of a
stop at low speeds, it may be caused by a
marginal wheel speed sensor signal. The sensor
air gap, tone wheel condition, and/or brakes
hanging up are possible causes of this condition.
9. After a road test in which no problems were
found, refer to any Technical Service Bulletins
that may apply.
5.0 REQUIRED TOOLS AND
EQUIPMENT
DRBIIIt(diagnostic read-out box)
jumper wires
ohmmeter
voltmeter
test light
6.0 GLOSSARY OF TERMS
ABS antilock brake system
BCM body control module
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CAB controller antilock brake
DC direct current
DLC data link connector
DRB diagnostic read-out box
DTC diagnostic test code
EVBP electronic variable brake proportion-
ing
HCU hydraulic control unit
I/C integrated circuit
ICU integrated control unit
IPM integrated power module
JBLK junction block
mA milli-Amp
PCI programmable communication inter-
face
P/M pump motor
TCS traction control system
VSS vehicle speed signal
WSS wheel speed sensor
7
GENERAL INFORMATION
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NOTES
8
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7.0
DIAGNOSTIC INFORMATION AND
PROCEDURES
9
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Symptom:
BATTERY VOLTAGE OUT OF RANGE
When Monitored and Set Condition:
BATTERY VOLTAGE OUT OF RANGE
When Monitored: Ignition On - Continuously
Set Condition: When the CAB detects battery voltage out of specified range on the ABS
Valve Fused B(+) circuit. Either the voltage is over 17.0 or under 7.5 volts on this circuit.
POSSIBLE CAUSES
INTERMITTENT DTC
BATTERY/CHARGING SYSTEM FAILURE
DAMAGED CAB/CAB HARNESS CONNECTOR
ABS VALVE FUSED B(+) CIRCUIT OPEN
GROUND CIRCUIT OPEN
CAB - INTERNAL FAULT
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, read DTC’s.
With the DRBIIIt, erase DTC’s.
Turn the ignition off.
Start the engine.
With the DRBIIIt, read DTC’s.
Does the DRBIIItdisplay BATTERY VOLTAGE OUT OF RANGE?
All
Yes →Go To 2
No →Go To 6
2 Turn the ignition off.
Perform a battery test and charging system test.
NOTE: Refer to service information for the related test(s)/symptom(s).
Does the battery and charging system pass?
All
Yes →Go To 3
No →Repair as neccessary.
Perform ABS VERIFICATION TEST - VER 1.
3 Turn the ignition off.
Disconnect the CAB harness connector.
Inspect the CAB and CAB harness connector for damage.
Is there any broken, bent, pushed out, corroded or spread terminals?
All
Yes →Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No →Go To 4
10
BRAKES (CAB)
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TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the CAB harness connector.
Measure the voltage of the ABS Valve Fused B(+) circuit.
Is the voltage above 10 volts?
All
Yes →Go To 5
No →Repair theABS Valve Fused B(+) circuit for an open. If the fuse is
open make sure to check for a short to ground.
Perform ABS VERIFICATION TEST - VER 1.
5 Turn the ignition off.
Disconnect the CAB harness connector.
Measure the resistance of the ground circuits.
Is the resistance below 5.0 ohms?
All
Yes →Replace the Controller Antilock Brake in accordance with the
Service Information.
Perform ABS VERIFICATION TEST - VER 1.
No →Repair the ground circuit(s) for an open.
Perform ABS VERIFICATION TEST - VER 1.
6 Turn the ignition off.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wire harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Refer to any Hotline letters or Technical Service Bulletins that may apply.
Were any problems found?
All
Yes →Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No →Test Complete.
11
BRAKES (CAB)
BATTERY VOLTAGE OUT OF RANGE — Continued
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Symptom:
BCM MESSAGES NOT RECEIVED
When Monitored and Set Condition:
BCM MESSAGES NOT RECEIVED
When Monitored: Ignition On - Continuously
Set Condition: When the CAB detects the BCM is not connected or not functioning
correctly for 10 seconds.
POSSIBLE CAUSES
ATTEMPT TO COMMUNICATE WITH THE BCM
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, attempt to communicate with the Body Control Module.
Was the DRBIIItable to I/D or communicate with the BCM?
All
Yes →Go To 2
No →Refer to the Communication category for the related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.
2 With the DRBIIIt, erase DTC’s.
Cycle the ignition switch from off to on and wait approximately 1 minute.
With the DRBIIIt, read DTC’s.
Did this DTC reset?
All
Yes →Replace the Body Control Module in accordance with the service
information.
Perform BODY VERIFICATION TEST - VER 1.
No →Test Complete.
12
BRAKES (CAB)
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Symptom:
CAB INTERNAL FAILURE
When Monitored and Set Condition:
CAB INTERNAL FAILURE
When Monitored: Ignition On - Continuously
Set Condition: When one of two internal CPUs, fails the programmed self test within the
CAB.
POSSIBLE CAUSES
INTERMITTENT DTC
DAMAGED CAB/CAB HARNESS CONNECTOR
FUSED RUN RELAY OUTPUT CIRCUIT OPEN
ABS VALVE FUSED B(+) CIRCUIT OPEN
ABS PUMP FUSED B(+) CIRCUIT OPEN
CAB - GROUND CIRCUIT OPEN
CAB - INTERNAL FAULT
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, read DTCs.
With the DRBIIIt, erase DTCs.
Turn the ignition off.
Turn the ignition on.
With the DRBIIIt, read DTCs.
Does the DRBIIItdisplay CAB INTERNAL FAILURE?
All
Yes →Go To 2
No →Go To 7
2 Turn the ignition off.
Disconnect the CAB harness connector.
Inspect the CAB/CAB harness connector for damage.
Is there any broken, bent, pushed out, corroded or spread terminals?
All
Yes →Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No →Go To 3
13
BRAKES (CAB)
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TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the CAB harness connector.
Turn the ignition on.
Measure the voltage of the Fused Run Relay Output circuit.
Is the voltage above 10 volts?
All
Yes →Go To 4
No →Repair the Fused Run Relay Output circuit for an open.
Perform ABS VERIFICATION TEST - VER 1.
4 Turn the ignition off.
Disconnect the CAB harness connector.
Measure the voltage of the ABS Valve Fused B(+) circuit.
Is the voltage above 10 volts?
All
Yes →Go To 5
No →Repair the ABS Valve Fused B(+) circuit for an open.
Perform ABS VERIFICATION TEST - VER 1.
5 Turn the ignition off.
Disconnect the CAB harness connector.
Measure the voltage of the ABS Pump Fused B(+) circuit.
Is the voltage above 10 volts?
All
Yes →Go To 6
No →Repair the ABS Pump Fused B(+) circuit for an open.
Perform ABS VERIFICATION TEST - VER 1.
6 Turn the ignition off.
Disconnect the CAB harness connector.
Measure the resistance of the ground circuits.
Is the resistance below 5.0 ohms?
All
Yes →Replace the Controller Antilock Brake in accordance with the
Service Information.
Perform ABS VERIFICATION TEST - VER 1.
No →Repair the ground circuit(s) for an open.
Perform ABS VERIFICATION TEST - VER 1.
7 Turn the ignition off.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wire harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Refer to any Hotline letters or Technical Service Bulletins that may apply.
Were any problems found?
All
Yes →Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No →Test Complete.
14
BRAKES (CAB)
CAB INTERNAL FAILURE — Continued
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Symptom:
INSTRUMENT CLUSTER BULB FAILURE
When Monitored and Set Condition:
INSTRUMENT CLUSTER BULB FAILURE
When Monitored: Ignition On - Continuously
Set Condition: When the mechanical instrument cluster informs the CAB that the ABS,
Brake, and TCS (if equipped) indicators failed and can’t be illuminated.
POSSIBLE CAUSES
INSTRUMENT CLUSTER OR ABS DTC PRESENT
CHECKING INSTRUMENT CLUSTER OPERATION
INSTRUMENT CLUSTER SELF-TEST
INSTRUMENT CLUSTER INTERNAL FAULT
CAB -- INTERNAL FAULT
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, read DTCs.
Are there any Instrument Cluster or ABS DTCs present?
All
Yes →Refer to the appropriate category for the related symptom(s).
Perform ABS VERIFICATION TEST - VER 1.
No →Go To 2
2 Turn the ignition off.
Perform the Key-on Bulb Check.
Does the ABS, Brake, or TCS (if equipped) indicators light and then go out after four
seconds?
All
Yes →Go To 3
No. Light remains after bulb check.
Go To 4
No. Indicator never comes on.
Go To 5
15
BRAKES (CAB)
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TEST ACTION APPLICABILITY
3 Turn the ignition off.
Turn the ignition on.
With the DRBIIIt, record and erase DTC’s.
NOTE: If you have other DTCs, repair other DTCs first before continuing.
Turn the ignition off.
Remove ABS Valve fuse.
Perform the Key-on Bulb Check.
Does the ABS, Brake, and TCS (if equipped) Indicators remain on after the 4 second
bulb check?
All
Yes →Reinstall theABS Valve fuse in the IPM. With the DRBIIIt, erase
Instrument Cluster DTCs. Test Complete.
Perform ABS VERIFICATION TEST - VER 1.
No →Go To 4
4 Reinstall the ABS Valve fuse, if removed.
Turn the ignition off.
Turn the ignition to RUN.
Perform the Instrument Cluster self test.
NOTE: Refer to Body information for the related test(s).
Did the indicators illuminate during the Instrument Cluster self test?
All
Yes →Replace the Controller Antilock Brake in accordance with the
Service Information.
Perform ABS VERIFICATION TEST - VER 1.
No →Go To 5
5 Turn the ignition off.
Turn the ignition to RUN.
Perform the Instrument Cluster self test.
NOTE: Refer to Body information for the related test(s).
Do the indicators turn on for 4 seconds, shut off for 5-10 seconds then illuminate?
All
Yes →Test Complete.
No →Replace the Instrument Cluster in accordance with the Service
Information.
Perform ABS VERIFICATION TEST - VER 1.
16
BRAKES (CAB)
INSTRUMENT CLUSTER BULB FAILURE — Continued
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Symptom List:
LEFT FRONT SENSOR CIRCUIT FAILURE
LEFT REAR SENSOR CIRCUIT FAILURE
RIGHT FRONT SENSOR CIRCUIT FAILURE
RIGHT REAR SENSOR CIRCUIT FAILURE
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be LEFT FRONT SENSOR CIRCUIT
FAILURE.
When Monitored and Set Condition:
LEFT FRONT SENSOR CIRCUIT FAILURE
When Monitored: Ignition On - Continuously
Set Condition: When the CAB detects a wheel speed sensor signal current is out of range.
LEFT REAR SENSOR CIRCUIT FAILURE
When Monitored: Ignition On - Continuously
Set Condition: When the CAB detects a wheel speed sensor signal current is out of range.
RIGHT FRONT SENSOR CIRCUIT FAILURE
When Monitored: Ignition On - Continuously
Set Condition: When the CAB detects a wheel speed sensor signal current is out of range.
RIGHT REAR SENSOR CIRCUIT FAILURE
When Monitored: Ignition On - Continuously
Set Condition: When the CAB detects a wheel speed sensor signal current is out of range.
POSSIBLE CAUSES
INTERMITTENT CONDITION
WHEEL SPEED SENSOR OR CONNECTOR DAMAGE
WHEEL SPEED SENSOR SIGNAL CIRCUIT FAULT
WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT SHORT TO GROUND
WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT OPEN
WHEEL SPEED SENSOR SIGNAL CIRCUIT SHORT TO GROUND
WHEEL SPEED SENSOR SIGNAL CIRCUIT OPEN
CAB - 12 VOLT SUPPLY CIRCUIT FAULT
CAB - SIGNAL CIRCUIT FAULT
WHEEL SPEED SENSOR 12 VOLT SUPPLY SHORT TO GROUND
17
BRAKES (CAB)
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POSSIBLE CAUSES
WHEEL SPEED SENSOR SIGNAL CIRCUIT INOPERATIVE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, read DTCs.
With the DRBIIIt, read and record Freeze Frame information.
With the DRBIIIt, erase DTCs.
Turn the ignition off.
Turn the ignition on.
With the DRBIIIt, read DTCs.
NOTE: The CAB must sense all four wheels at 25km/h (15 mph) before it will
extinguish the ABS indicators.
Does the DRBIIItdisplay SENSOR CIRCUIT FAILURE?
All
Yes →Go To 2
No →Go To 13
2 Turn the ignition off.
Inspect the CAB connector, affected Wheel Speed Sensor, and affected Wheel Speed
Sensor connector.
Is the affected Wheel Speed Sensor or any of the connector(s) damaged?
All
Yes →Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No →Go To 3
3 Turn the ignition off.
Disconnect the affected Wheel Speed Sensor connector.
Note: Check connector - Clean/repair as necessary.
Turn the ignition on.
Measure the voltage between affected Wheel Speed Sensor 12 Volt Supply circuit and
ground.
Is the voltage above 10 volts?
All
Yes →Go To 6
No →Go To 4
4 Turn the ignition off.
Disconnect the CAB harness connector.
Disconnect the affected Wheel Speed Sensor connector.
Using a 12-volt test light connected to 12-volts, probe the affected Wheel Speed
Sensor 12 Volt Supply circuit.
Does the test light illuminate?
All
Yes →Repair the affected Wheel Speed Sensor 12 Volt Supply circuit for
a short to ground.
Perform ABS VERIFICATION TEST - VER 1.
No →Go To 5
18
BRAKES (CAB)
LEFT FRONT SENSOR CIRCUIT FAILURE — Continued
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